1. Field of the Invention
The present invention is directed to a messaging system and/or method which enables short messages, for example, but not limited to audio messages, to be transmitted from one user of the system or method to another user of the system or method on an asynchronous, non-interrupt basis using, for example, internet connectivity as a network medium. Push To Talk functionality is combined with an asynchronous, non-interruptive protocol that allows a user of the system to download messages, such as, but not limited to, audio messages, for listening or viewing on a handheld device such as a mobile phone.
2. Background Art
Various communication systems utilizing Push to Talk (“PTT”) functionality have been known in the art. For example, U.S. Pat. No. 7,107,017 (2006) to Koskelainen et al. teaches a system, apparatus, and method for introducing services into a PTT environment. Requests for services are generated and transmitted via requesting PTT clients. The request is received at a PTT server, which forwards the request to a PTT application server recognized by the PTT server as another PTT client. The requested service is performed at the PTT application server, and a result is generated in response. The result is transmitted from the PTT application server to the requesting PTT client by way of the PTT server.
Another example PTT system is taught in U.S. Pat. No. 7,170,863 to Denman et al. (2007) which discloses a system and method for PTT service to another user via a wireless packet data network. One embodiment of the system taught in this U.S. patent includes a packet data network with at least one mobile station, a radio access network, a database server, a registrar and location server, an Interactive Multimedia Server (IMS), and a PTT server that provides PTT service to other PTT users on the packet network.
Still another system utilized for PTT services and incorporating geolocation functionality is taught in U.S. Pat. No. 7,546,134. This U.S. patent discloses a processor configured to detect a PTT event and trigger a location operation responsive to the PTT event. According to one exemplary embodiment, the processor determines a location of the wireless communication device and/or one or more remote wireless communication devices when the processor detects a floor control event. According to another embodiment of the 7,546,134 invention, the processor determines a location of the wireless communication device and/or one or more remote wireless communication devices when the processor detects a session entrance event. As a result, a user may use location information about the wireless communication device and/or a remote wireless communication device to facilitate PTT communications.
Most PTT implementations are half duplex communication systems which, by definition, allow only one user to transmit at a time. Because only one user can transmit at a time, there must necessarily exist a protocol for determining which user of such PTT systems has authority to transmit and which user does not have authority to transmit at any given time. This control of transmit authority is generally termed “floor control”. Floor control can become a complicated protocol in group PTT applications and may require a complicated scheme of token passing, handshaking, or other methods for determining which user of the system has transmit authority. A drawback of current PTT systems is that they operate in real time, which means the users of such systems must participate in the communication as it is occurring. This real time requirement causes the PTT system to be interruptive in nature because it requires the user to focus on the messaging at the time the messaging occurs. If an intended recipient is not active in the PTT exchange, that user will miss the intended message. Because of the nature of PTT systems, users of such systems must cease other activities at the time of message exchange in order to focus on receipt of messages intended for them. Such interruptive communication can be distracting, and even dangerous, in certain work environments. The present invention overcomes this disadvantage of the prior art.
Furthermore, traditional PTT systems transmit voice data directly between mobile devices rather than mediating through an intermediate message broker. Such PTT systems have low latency and responsiveness, but as a consequence of this design, users that are offline will not be able to receive messages addressed to them. These systems have other drawbacks, such as being susceptible to network interference and exposing private information in the form of network addresses.
Voice messaging systems such as voice mail have existed for decades. Such voice mail systems are typically implemented on either a landline or cellular network, or may be internet based, as in, for instance, Voice over IP (VoIP) systems. Such voice messaging systems store messages intended for recipients that are offline. However, voice mail systems use a wholly different mechanism for real-time communication (in other words, a phone call) than they do for retrieval of stored messages, which is done using either a visual interface or a menu-based dial-in system. This prevents users from receiving messages as they are being recorded, and requires them to shift communication modalities when listening to a live conversation vs. a recorded message. Some PBX voice mail systems allow an authorized user to listen to voice messages while they are being recorded, however this always requires a different modality than a normal conversation.
Furthermore, text messaging systems, or Short Messaging Systems (SMS), are well known for the transmission and receipt of short text messages using the cellular telephone backbone. These systems, while useful and non-interruptive, do not allow for communication of non-text parameters such as speech inflection, pauses or changes in rate of speech, and other variation in speech patterns which can be extremely important in interpersonal communication. Text message systems also require focus and concentration upon the keyboard of the mobile client device and therefore require both visual and tactile concentration, which can prohibit the user from effectively completing other tasks such as driving an automobile, performing physical tasks, or even walking.
What is needed, then, is an internet-based system for short message communication that, among other things, allows for the transmission and playback of short audio messages on an asynchronous basis while at the same time requiring minimal tactile interaction with the user of a mobile device and providing privacy in the form by concealing network addresses. Such asynchronous communication would allow the recipient to download and playback short audio messages at the time and place of their choosing, would allow for non-interruptive communications, and would allow for the use of voice inflection and similar parameters to increase the effectiveness of communication over text-based systems. Such a system would also allow offline users to retrieve messages at their convenience: i.e. it would allow users of the system to receive their messages without necessitating their participation in the conversation on a real-time basis.